Nedocromil sodium reduces cigarette smoke-induced bronchoconstrictor hyperresponsiveness to substance P in the guinea-pig.
نویسندگان
چکیده
Acute exposure to cigarette smoke provokes airway hyperresponsiveness to substance P and inactivates neutral endopeptidase (NEP). To determine whether nedocromil sodium can prevent cigarette smoke-induced hyperresponsiveness to substance P, we studied two groups of anaesthetized guinea-pigs. One group of guinea-pigs was pretreated with aerosolized 0.9% NaCl solution (90 breaths), the other group was pretreated with aerosolized nedocromil sodium (10(-4) M, 90 breaths). In each animal, pretreatment was followed by either exposure to the smoke of one cigarette or exposure to air. After acute exposure to cigarette smoke or to air, we measured the change in total pulmonary resistance (RL) induced by increasing concentrations of aerosolized substance P. In the absence of nedocromil sodium, the bronchoconstrictor responses to substance P were greater in cigarette smoke-exposed guinea-pigs than in air-exposed animals. Aerosolized nedocromil sodium had no effect on the response to substance P in air-exposed animals, but it reduced cigarette smoke-induced hyperresponsiveness to substance P. The preventive effect on cigarette smoke-induced hyperresponsiveness to substance P was observed at concentrations of aerosolized nedocromil sodium of 3 x 10(-5), 10(-4), and 3 x 10(-4) M. In vitro, cigarette smoke solution inhibited NEP activity from lung membrane preparations, but this inhibitory effect was not modified by nedocromil sodium (10(-4) M). We conclude that aerosolized nedocromil sodium reduces cigarette smoke-induced airway hyperresponsiveness to substance P in vivo. This action of nedocromil sodium is not due to a protective effect on cigarette smoke-induced inactivation of NEP in vitro.
منابع مشابه
Effect of Sodium Valproate on Ouabain-Induced Arrhythmia in Isolated Guinea-Pig Atria
Sodium valproate (SV), an antiepileptic drug has several mechanism of action. It inhibits voltage sensitive Na+ channels and reduces intracellular Na accumulation. These actions are similar to that of both phenytoin and carbamazepine. We have investigated the direct cardiac action of SV and its effects on ouabain-induced arrhythmia in isolated guinea-pig atria. The guinea-pig atrium was dissect...
متن کاملRelation of smoking to immunoreactive endothelin in the bronchiolar epithelial cells.
BACKGROUND Endothelin is a potent bronchoconstrictor which appears to be important in asthma. To ascertain whether cigarette smoking is associated with any alteration in the proportion of bronchiolar epithelial cells which express endothelin immunoreactivity, the airways in the lungs of non-smokers and smokers were analysed. Since an increase in immunoreactivity has been found in the bronchial ...
متن کاملNeurokinin B- and specific tachykinin NK(3) receptor agonists-induced airway hyperresponsiveness in the guinea-pig.
1. The aim of this study was to determine whether neurokinin B (NKB) or specific agonists of tachykinin NK(3) receptors, [MePhe(7)]NKB and senktide, were able to induce airway hyperresponsiveness in guinea-pigs. The effects of these compounds were compared to those of substance P (SP), neurokinin A (NKA) and the preferential tachykinin NK(1) ([Sar(9), Met(0(2))(11)]SP) or NK(2) ([betaAla(8)]NKA...
متن کاملModulation of the bronchial inflammation in sensitized guinea-pigs by FK506, nedocromil sodium and dexamethasone.
Guinea-pigs sensitized by a subcutaneous injection of ovalbumin in Al(OH)3 and boosted 2 weeks later exhibit marked bronchial hyperresponsiveness to various agonists and intense bronchial wall infiltration by CD4+ T-lymphocytes and eosinophils. We have compared the effect of FK506, a novel immunosuppressive agent, on the mucosal infiltration by T-cells and eosinophils with the well established ...
متن کاملEffects and interactions of opioids on plasma exudation induced by cigarette smoke in guinea pig bronchi.
The effects of opioids on cigarette smoke-induced plasma exudation were investigated in vivo in the main bronchi of anesthetized guinea pigs, with Evans blue dye as a plasma marker. Acute inhalation of cigarette smoke increased plasma exudation by 216% above air control values. Morphine, 0.1-10 mg/kg but not 30 mg/kg, inhibited the exudation but had no significant effect on substance P-induced ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The European respiratory journal
دوره 8 1 شماره
صفحات -
تاریخ انتشار 1995